Myopia controlling ophthalmic lenses

ABSTRACT

Lenses are designed using the corneal topography or wavefront measurements of the eye derived by subtracting the optical power of the eye after orthokeratology treatment from the optical power before orthokeratology treatment.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of application Ser. No. 12/821,927,filed Jun. 23, 2010 which claims the benefit of Provisional ApplicationNo. 61/220,487 filed Jun. 25, 2009.

BACKGROUND OF THE INVENTION

This invention relates to designs and methods for preventing, stoppingor slowing myopia progression.

Myopia, also known as short-sightedness, is a refractive conditionwherein the overall power of the eye is too high, or too strong, causinglight from distant objects to focus in front of the retina. This isperceived by the viewer as blurring of distant objects, with the amountof blurring being related to the severity of the myopia. This conditionis often first seen in childhood, and usually noticed at school age. Aprogression, or increase, in the severity of myopia, is usually seen inmyopic cases until young adulthood.

U.S. Pat. No. 6,045,578 proposes methods of using on-axis longitudinalspherical aberration (LSA) in contact lens designs to attempt to haltmyopia progression. The design approach suggested does not appear toaddress specific wavefront/refractive power characteristics of theindividual eye/or group average data or changes in pupil size associatedwith close work.

U.S. Pat. No. 7,025,460 proposes methods of altering field curvature(off-axis focal point variation) to try to halt myopia progression. Themathematics behind this approach uses “extended conics” where the simpleconic equations have even ordered polynomial terms added to them. Theseconic and polynomial terms are processed so that the contact lenssurface shape of the proposed design produces the required amount offield curvature.

US 2003/0058404 and US 2008/0309882 proposes a method of measuring thewavefront of the eye and correcting the wavefront of the eye with acustomized correction to slow myopia progression. Pupil size changesassociated with near tasks were not an aspect of the design process.

EP 1853961 proposes the measurement of the wavefront before and afternear work. The changes in wavefront aberrations are then corrected witha custom contact lens. Group or population data to create a design tocontrol eye growth are not included.

“Orthokeratology Alters Aberrations of The Eye”, Optometry and VisionScience, May 2009. The article discusses higher order aberrations of theeye associated with orthokeratology.

A more complete approach to slowing or stopping myopia progression isstill desired. This is addressed in this specification.

SUMMARY OF THE INVENTION

In one aspect of the invention a method and resulting design to be usedin the fabrication of ophthalmic lenses useful in controlling andslowing the progression of myopia incorporates the use of cornealtopographic data from the eye. Ophthalmic lenses include, for example,contact lenses, intraocular lenses, corneal inlays, and corneal onlays.

In another aspect of the invention the method and resulting designs tobe used in the fabrication of ophthalmic lenses useful in controllingand slowing the progression of myopia incorporates the use of wavefrontdata from the eye.

In yet another aspect of the invention, a design for an ophthalmic lensproduced according to the methods of the invention includes a convexsurface with a central optic zone surrounded by a peripheral zone whichis further surrounded by an edge zone, and a concave surface which restson the wearer's eye; the central optic zone containing an inner disc,and a plurality of annuli; and a lens power at any location in theoptical zone is described by subtracting the optical power of the eyeafter orthokeratology treatment from the optical power beforeorthokeratology treatment; the lenses made using these designs areuseful in controlling or slowing the progression of myopia.

In another aspect of the invention, a method to generate an ophthalmiclens design includes the steps of acquiring corneal topographic databefore and after orthokeratology treatment, converting the cornealtopographic data to radial power maps, subtracting the post from the pretreatment map and generating a lens power profile.

In another aspect of the invention, a method to generate an ophthalmiclens design includes the steps of acquiring wavefront data before andafter orthokeratology treatment, converting the wavefront data torefractive power maps, subtracting the post from the pre treatment mapand generating a lens power profile.

In yet another aspect of the invention, data for the total population isconsidered.

In yet another aspect of the invention, data for a sub-population isconsidered.

In yet another aspect of the invention, data for an individual subjectis considered.

In yet another aspect of the invention, data is an averaged overmultiple files.

In yet another aspect of the invention, the lens design power profile iscalculated by averaging all meridians to a rotationally symmetric form.

In yet another aspect of the invention, the lens design power profile iscalculated by averaging individual meridians to a non-rotationallysymmetric form.

In yet another aspect of the invention, methods of designing lenses forslowing myopia progression are encoded into instructions such as machineinstructions and are programmed into a computer.

In yet another aspect of the invention, articles include executableinstructions for designing lenses for slowing myopia progression; themethod includes converting corneal topographic data characterizing aneye to a radial power map, generating a lens power profile and using thepower profile to produce a lens design for a lens with a convex surfacewith a central optic zone surrounded by a peripheral zone which isfurther surrounded by an edge zone, and a concave surface which rests onthe wearer's eye; the central optic zone containing an inner disc, and aplurality of annuli; the lens power at any location in the optical zoneis described by subtracting the optical power of the eye afterorthokeratology treatment from the optical power before orthokeratologytreatment.

In yet another aspect of the invention, articles include executableinstructions for designing lenses for slowing myopia progression; themethod includes converting wavefront data characterizing an eye to arefractive power map, generating a lens power profile and using thepower profile to produce a lens design for a lens with a convex surfacewith a central optic zone surrounded by a peripheral zone which isfurther surrounded by an edge zone, and a concave surface which rests onthe wearer's eye; the central optic zone containing an inner disc, and aplurality of annuli; the lens power at any location in the optical zoneis described by subtracting the optical power of the eye afterorthokeratology treatment from the optical power before orthokeratologytreatment.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows the averaged pre treatment corneal topography maps of agroup of 26 subjects prior to orthokeratology.

FIG. 2 shows the averaged post treatment corneal topography maps of agroup of 26 subjects subsequent to orthokeratology.

FIG. 3 shows the difference between the averaged post and pre treatmentcorneal topography maps of a group of 26 subjects having undergoneorthokeratology treatment.

FIG. 4 shows the difference between the averaged post and pre treatmentcorneal topography maps of a group of 26 subjects having undergoneorthokeratology treatment, truncated to a diameter of 6 mm.

FIG. 5 shows the power profile of a lens design, according to theinvention.

FIG. 6 shows the envelope of design profiles based upon scaling of theaverages all of the meridians in the example above, according to theinvention.

DETAILED DESCRIPTION

Orthokeratology (sometimes called corneal refractive therapy) is thepractice of fitting rigid contact lenses to deliberately alter the shapeof the central cornea. By making the central cornea flatter incurvature, the optical power of the cornea (and therefore total eye)decreases. This has the effect of reducing the degree of myopia of theeye. Specially designed rigid contact lenses are typically wornovernight (during sleep) and removed in the morning. The pressureexerted by the rigid lens on the cornea during sleep, temporarilyflattens the central cornea. This flattening leads to a reduction ofmyopia which gradually regresses (i.e. the cornea returns to its normalshape) over the next 1 to 3 days. The orthokeratology patient wears therigid lens during sleep every 1 to 3 nights, depending upon the rate ofregression and thereby maintains a reduced level of myopia during thewaking hours (without the need to wear any form of contact lenses orspectacles).

An unintended consequence of orthokeratology has been the reduction ofthe rate of myopia progression in patients using this form of myopiacorrection. Studies by Cho et al (LORIC study) and Walline et al (CRAYONstudy) have both shown that patients wearing orthokeratology lenses notonly have a reduction in myopia, but a reduction in the rate of myopiaprogression (i.e. eye growth). A likely explanation for this reductionin the rate of myopia progression is the optical changes induced in thecornea by orthokeratology. In effect, orthokeratology changes thecorneal optics so that the central refractive power is more minus (lesspositive), while the peripheral corneal power is more positive (lessminus).

In a preferred embodiment, the methods of the invention involve usingcorneal topography data to design and produce contact lenses useful fortreating, slowing, and sometimes stopping the progression of myopia.Corneal topography data is collected from a patient using avideokeratoscope such as a Keratron or Keratron Scout (Optikon 2000;Rome, Italy). This topographic data is available in several formats. Thepreferred format in the present invention is to depict the cornea as arefractive power data.

FIG. 1 shows the average corneal refractive power of 26 eyes prior toorthokeratology as measured by a videokeratoscope, and FIG. 2 shows avideokeratoscope image of the same 26 eyes after treatment byorthokeratology. The change in corneal power is derived by subtractingthe refractive power of the cornea before and after orthokeratology.This map of refractive power change shows the central shift of power inthe minus direction (i.e. blue colors) and the peripheral shift inpowers in the positive direction (i.e. red colors), and is shown in FIG.3. The difference map is the basis for the design power profile reportedherein, and will control the rate of myopia progression.

In one embodiment, these maps are centered around the videokeratoscopeaxis (the axis at which the videokeratoscope measures the cornealshape), however in a preferred embodiment they could also be resampledand centered around the pupil of the eye (i.e. the entrance pupil of theeye at the corneal plane). The pupil center and videokeratoscope axisrarely coincide. In terms of optical design, it is preferable to centerthe optical design along the axis of the entrance pupil center.

The next step in the process of deriving the soft lens optical design isto reduce the two-dimensional refractive power difference map into anaverage power change of all of the meridians averaged together,resulting in a symmetric average power map. FIG. 4 illustrates thisprocess for a two dimensional refractive power difference map, limitedto a diameter of 6 mm.

In an alternate embodiment, the power difference map is reduced to atwo-dimensional refractive power difference map by averaging the powerchange of each of the meridians, the individual meridians being averagedseparately, resulting in a non-rotationally symmetric average power map.

In a preferred embodiment, it is desirable to extend the design powerprofile beyond the 6 mm limitation out to 8 mm, and to create a powerprofile which provides for a better clinical outcome and helps toprevent providing excessive amounts of plus optical power to the wearer.In a preferred embodiment, the plus optical power is first decreased andthen leveled off.

In a preferred embodiment, a design for an ophthalmic lens producedaccording to the methods of the invention includes a convex surface witha central optic zone surrounded by a peripheral zone which is furthersurrounded by an edge zone, and a concave surface which rests on thewearer's eye; the central optic zone containing an inner disc, and aplurality of annuli; and a lens power at any location in the opticalzone is described by subtracting the optical power of the eye afterorthokeratology treatment from the optical power before orthokeratologytreatment; the lenses made using these designs are useful in controllingor slowing the progression of myopia.

FIG. 5 shows the power profile of a preferred embodiment. In thispreferred embodiment, the central optic zone contains an inner disc,with the range of usable diameter between 0 and 2 mm, the preferreddiameter about 1.5 mm; a first annulus with an outer diameter between6.0 to 7.0 mm, the preferred diameter about 6.5 mm; a second annulussurrounding the first annulus with an outer diameter between 7.25 and7.75 mm, the preferred diameter about 7.5 mm; and a third annulussurrounding the second annulus, with a diameter between 7.5 and 8.5 mm,the preferred diameter being 8 mm.

The optical power shown in FIG. 5 is based upon the reduction of datafor a population mean. The powers shown would be added to the initialdistance prescription of the wearer. The optical power in the centraldisc of the optic zone is substantially constant; the optical power inthe first annulus, at a diameter of 4 mm increases in plus power to arange of +0.5 to +1.5 diopters, with a preferred value of about +1.0diopter, at a diameter of 6.5 mm has increased in plus value to a rangeof +1.5 to +5.5 D, with a preferred value of about +3.4 D; the opticalpower in the second annulus decreasing smoothly from the power found atthe edge of the first annulus to a power between about +1.5 and +4.5 D,with a preferred value of about +3.0 D; the optical power of the thirdannulus being substantially constant at about the power found at theedge of the second annulus.

Distance refractive prescription powers that are substantially differentthan −3.00 D may require scaling of the power profile. FIG. 6 shows apreferred embodiment of a scaled envelope of resultant refractive powercurves that can be calculated and applied to a lens design from theaveraged data shown above. It is thus advantageous with this inventivedesign to create a family of design power profiles. These are created byproportionally multiplying a scaling factor for each point in theaperture; the range of the scaling factor between 0.25 and 4, 0.5 to 1.5being the preferred range.

The preferred process steps for generating a lens design power profileby this method are as follows:

-   -   1) Acquire and average corneal topography refractive power data        maps for eyes pre orthokeratology treatment,    -   2) Acquire and average corneal refractive power data maps for        eyes post orthokeratology treatment,    -   3) Subtract the pre treatment from the post treatment maps,    -   4) Average all of the meridians together to generate a        rotationally symmetric power map.    -   5) Alternately average the individual meridians together to        generate a non-rotationally symmetric power map.    -   6) Trim the maps to a convenient uniform diameter,    -   7) Optionally extend the profile out to a larger diameter by        decreasing the plus optical power and then flat leveling the        power.    -   8) Optionally generate an envelope of average resultant power        profiles by proportional scaling.

In an alternate embodiment, the methods of the invention involve usingwavefront data to design and produce contact lenses useful for treating,slowing, and sometimes stopping the progression of myopia. Ocularwavefront data is collected from a patient using a wavefront sensor suchas a COAS (wavefront Sciences Inc, Albuquerque N. Mex.). This wavefrontdata is generally in the form of Zernike polynomial coefficients but canalso be a set of wavefront heights at specified Cartesian or polarcoordinates. A preferred system to designate the Zernike coefficientshas been described as the OSA method, in ANSI Z80.28.

The preferred process steps for generating a lens design power profileby this method are as follows:

-   -   1) Acquire and average ocular wavefront data maps for eyes prior        to orthokeratology treatment. Each wavefront is converted to a        refractive power map by calculating the powers based upon the        radial slopes in the direction of the z axis, defined as the        front to back axis, e.g. along the visual axis through the pupil        center.    -   2) Acquire and average ocular wavefront data maps for eyes post        orthokeratology treatment. Each wavefront is converted to a        refractive power map by estimating the radial slopes in the        direction of the z axis, defined as the front to back axis, e.g.        along the visual axis through the pupil center.    -   3) Subtract the pre treatment from the post treatment maps.    -   4) Average all of the meridians together to generate a        rotationally symmetric power map.    -   5) Alternately average the individual meridians together to        generate a non-rotationally symmetric power map.    -   6) Trim the maps to a convenient diameter    -   7) Optionally extend the profile out to a larger diameter by        decreasing the optical power and then flat leveling the power.    -   8) Optionally generate an envelope of average resultant power        profiles by proportional scaling.

In this method, a refractive power map is calculated from the set ofestimated wavefront Zernike coefficients using the refractive Zernikepower polynomials, Ψ_(j)(ρ,θ), as follows (see Iskander et al., 2007,attached)

$\begin{matrix}{{\hat{F}( {r,\theta} )} = {\frac{10^{3}}{r_{\max}}{\sum\limits_{j = 3}^{P - 1}{c_{j}{\Psi_{j}( {{r/r_{\max}},\theta} )}}}}} & (1)\end{matrix}$where c_(j) are the wavefront Zernike polynomial coefficients, r_(max)corresponds to the pupil radius,

$\begin{matrix}{\mspace{79mu}{{\Psi_{j}( {\rho,\theta} )} = \{ {\begin{matrix}{{\sqrt{2( {n + 1} )}{Q_{n}^{m}(\rho)}{\cos( {m\;\theta} )}},} & {m > 0} \\{{\sqrt{2( {n + 1} )}{Q_{n}^{m}(\rho)}{\sin( {m\;\theta} )}},} & {m < 0} \\{\sqrt{n + 1}{Q_{n}^{m}(\rho)}} & {m = 0}\end{matrix}\mspace{79mu}{with}} }} & (2) \\{{{Q_{n}^{m}(\rho)} = {\sum\limits_{s = 0}^{{{({n - {m}})}/2} - q}{\frac{( {- 1} )^{s}{( {n - s} )!}( {n - {2s}} )}{{s!}{( {{( {n + {m}} )/2} - s} )!}{( {{( {n - {m}} )/2} - s} )!}}\rho^{n - {2s} - 2}}}}\mspace{79mu}{and}\mspace{79mu}{q = \{ {\begin{matrix}{1,} & {{m} \leq 1} \\{0,} & {otherwise}\end{matrix}.} }} & (3)\end{matrix}$

Other methods are known by those skilled in the art to generate orcalculate refractive power values from wavefront data. Ocular pupilsizes are also estimated either directly from the wavefront measurementor by an independent pupil measurement (e.g. using a pupillometer). Ifthe pupil is measured independently of the wavefront, it should bemeasured under similar lighting conditions.

The method can be used to design lenses for individuals on a custom lensbasis or averaged for populations, or sub-populations. This method canbe used to produce a rotationally symmetric design where all optic zonemeridians are the same, or a non-rotationally symmetric design whereeach meridian is unique and the result of the analysis of comparingtopography or wavefront before and after orthokeratology.

The ophthalmic lens made according to the invention has the followingparts and characteristics:

-   -   a) a convex surface with a central optic zone surrounded by a        peripheral zone which is further surrounded by an edge zone, and        a concave surface which rests on the patient's eye;    -   b) the lens power at any location in the optical zone is        described by subtracting the optical power of the eye after        orthokeratology treatment from the optical power before        orthokeratology treatment.

In another preferred embodiment, the ophthalmic lens made according tothe invention has the following parts and characteristics:

-   -   a) A central optic zone, the central optic zone contains an        inner disc, with the range of usable diameter between 0 and 2        mm, the preferred diameter about 1.5 mm;    -   b) a first annulus with an outer diameter between 6.0 to 7.0 mm,        the preferred diameter about 6.5 mm;    -   c) a second annulus surrounding the first annulus with an outer        diameter between 7.25 and 7.75 mm, the preferred diameter about        7.5 mm;    -   d) a third annulus surrounding the second annulus, with a        diameter between 7.5 and 8.5 mm, the preferred diameter being        about 8.0 mm.

In another preferred aspect of the present invention, the ophthalmiclens made according to the invention has the following parts andcharacteristics:

-   -   a) The optical power in the central disc of the optic zone is        substantially constant;    -   b) the optical power in the first annulus at about a diameter of        4 mm increases in plus power to a range of +0.5 to +1.5 D, with        a preferred value of about +1.0 D, at a diameter of 6.5 mm        increases in plus power to a range +1.5 to +5.5 D, with a        preferred value of about +3.4 D;    -   c) the optical power in the second annulus decreasing smoothly        from the power found at the edge of the first annulus to a power        between +1.5 and +4.5 D, with a preferred value of about +3.0 D;    -   d) the optical power of the third annulus being substantially        constant at about the power found at the edge of the second        annulus.

In another preferred aspect of the present invention, the ophthalmiclens made according to the invention has the following parts andcharacteristics:

-   -   a) The optical power in the central disc of the optic zone is        substantially constant;    -   b) the optical power in the first annulus increases in plus        power by a suitable polynomial equation of 4^(th) order or        higher;        -   in a preferred aspect, the power change in the first annulus            is governed by the equation:            Power=0.486x ⁶−5.8447x ⁵+27.568x ⁴−65.028x ³+81.52x            ²−51.447x+12.773            where x is the radial distance from the center of the lens.    -   c) the optical power in the second annulus decreasing from the        power found at the edge of the first annulus to a power between        +1.5 and +4.5 D, with a preferred value of about +3.0 D;    -   d) the optical power of the third annulus being substantially        constant at about the power found at the edge of the second        annulus.

It is recognized by those skilled in the art that the power in thecentral optical zone of the lens is a result of the powers of the backsurface and front surface working together. The variations in powerdescribed by the method and design of the present invention may beapplied to the front surface, back surface, or any combination thereof.In a preferred embodiment, the power variations described by the methodand design of the present invention are applied to the front surface.

Power Profile Driven Ophthalmic Lens Design Methods:

Different data sources can be used to derive a contact lens design formyopia control. Examples include:

A customized design based on the individual subjects data, or

A group design based on a particular sub-population of data (e.g. youngAsian children aged 10-16 years of age), or

A general population design based on all available data (e.g. allmyopes).

Additionally, both rotationally symmetric designs or non-rotationallysymmetric designs are obtainable using the method of the invention. Whendata is averaged across all considered semi-meridians or it can be usedto create rotationally symmetrical designs, or if the data is retainedin its semi-meridional form it can be used to create non-rotationallysymmetric designs. Non-rotationally symmetric correction forms include,but are not limited to toric, sphero-cylindrical, sphero-cylindricalwith higher order aberration correction. Toric includes the correctionof both regular and irregular astigmatism.

The following is an exemplary design method pursuant to the presentinvention, obtained using averaged data from all of the consideredsemi-meridians. This approach will result in a rotationally symmetricdesign.

Method 1:

In the first method, pre and post orthokeratology maps are used as thestarting point for the design. The pre orthokeratology map is subtractedfrom the post, and then the meridians are averaged. This will create thepower profile shown in FIG. 5. This power profile is then applied to thebase design of a lens for a myope requiring a −3.00 DS lens, to retardthe advance of myopia. In method 1, the design power of the firstannulus within the central optical zone was calculated mathematically asfollows:Power=0.486x ⁶−5.8447x ⁵+27.568x ⁴−65.028x ³+81.52x ²−51.447x+12.773where x is the radial distance from the center of the lens.

The methods of the invention can be embodied as computer readable codeon a computer readable medium. The computer readable medium is any datastorage device that can store data, which thereafter can be read by acomputer system. Examples of computer readable medium include read-onlymemory, random-access memory, CD-ROMs, DVDs, magnetic tape, optical datastorage devices. The computer readable medium can also be distributedover network coupled computer systems so that the computer readable codeis stored and executed in a distributed fashion.

The invention may be implemented using computer programming orengineering techniques including computer software, firmware, hardwareor any combination or subset thereof. Any such resulting program, havingcomputer-readable code means, may be embodied or provided within one ormore computer-readable media, thereby making a computer program product,i.e., an article of manufacture, according to the invention. Thecomputer readable media may be, for example, a fixed (hard) drive,diskette, optical disk, magnetic tape, semiconductor memory such asread-only memory (ROM), etc., or any transmitting/receiving medium suchas the Internet or other communication network or link. The article ofmanufacture containing the computer code may be made and/or used byexecuting the code directly from one medium, by copying the code fromone medium to another medium, or by transmitting the code over anetwork.

Devices according to the invention may also be one or more processingsystems including, but not limited to, a central processing unit (CPU),memory, storage devices, communication links and devices, servers, I/Odevices, or any sub-components of one or more processing systems,including software, firmware, hardware or any combination or subsetthereof, which embody the invention as set forth in the claims.

User input may be received from the keyboard, mouse, pen, voice, touchscreen, or any other means by which a human can input data to acomputer, including through other programs such as application programs.

One skilled in the art of computer science will readily be able tocombine the software created as described with appropriate generalpurpose or special purpose computer hardware to create a computer systemor computer sub-system embodying the method of the invention.

The methods embodied in, for example, the computer instructions oncomputer readable media are used to produce the designs described above.The designs created according to one of the methods described above areused to produce lenses. Preferably, the lenses are contact lenses.Illustrative materials for formation of soft contact lenses include,without limitation, silicone elastomers, silicone-containing macromersincluding, without limitation, those disclosed in U.S. Pat. Nos.5,371,147, 5,314,960, and 5,057,578 incorporated in their entireties byreference, hydrogels, silicone-containing hydrogels, and the like andcombinations thereof. More preferably, the surface is a siloxane, orcontains a siloxane functionality including, without limitation,polydimethyl siloxane macromers, methacryloxypropyl siloxanes, andmixtures thereof, silicone hydrogel or a hydrogel. Illustrativematerials include, without limitation, acquafilcon, etafilcon,genfilcon, lenefilcon, senefilcon, balafilcon, lotrafilcon, galyfilconor narafilcon.

Curing of the lens material may be carried out by any convenient method.For example, the material may be deposited within a mold and cured bythermal, irradiation, chemical, electromagnetic radiation curing and thelike and combinations thereof. Preferably, molding is carried out usingultraviolet light or using the full spectrum of visible light. Morespecifically, the precise conditions suitable for curing the lensmaterial will depend on the material selected and the lens to be formed.Suitable processes are disclosed in U.S. Pat. Nos. 4,495,313, 4,680,336,4,889,664, 5,039,459, and 5,540,410 incorporated herein in theirentireties by reference.

The contact lenses of the invention may be formed by any convenientmethod. One such method uses a lathe to produce mold inserts. The moldinserts in turn are used to form molds. Subsequently, a suitable lensmaterial is placed between the molds followed by compression and curingof the resin to form the lenses of the invention. One ordinarily skilledin the art will recognize that any other number of known methods may beused to produce the lenses of the invention.

EXAMPLES Example 1 (Prophetic)

In a longitudinal study comparing the axial length (eye growth) andauto-refraction of an age matched pediatric population of subjects aged6 to 14 yrs old, contact lenses produced according to the method anddesign of the present invention are fitted to one group while a controlgroup wears conventional contact lenses or spectacles. The first groupreceives lenses according to the following lens design and optical powerprofile described herein.

-   -   a) The optical power in the central disc of the optic zone is        substantially constant;    -   b) the optical power in the first annulus at about a diameter of        4 mm increases in plus power to a range of +0.5 to +1.5 D, with        a preferred value of about +1.0 D, at a diameter of 6.5 mm        increases in plus power to a range +1.5 to +4.5 D, with a        preferred value of about +3.4 D;    -   c) the optical power in the second annulus decreasing from the        power found at the edge of the first annulus to a power between        +1.5 and +4.5 D, with a preferred value of about +3.0 D;    -   d) the optical power of the third annulus being substantially        constant at about the power found at the edge of the second        annulus.

The lens powers in this example are described as follows:

-   -   a) The optical power in the central disc of the optic zone is        substantially constant;    -   b) the optical power in the first annulus increases in plus        power by a suitable polynomial equation of 4^(th) order or        higher;    -   c) in a preferred aspect, the power change in the first annulus        is governed by the equation:        Power=0.486x ⁶−5.8447x ⁵+27.568x ⁴−65.028x ³+81.52x        ²−51.447x+12.773        where x is the radial distance from the center of the lens.    -   d) the optical power in the second annulus decreasing from the        power found at the edge of the first annulus to a power between        +1.5 and +4.5 D, with a preferred value of about +3.0 D;    -   e) the optical power of the third annulus being substantially        constant at about the power found at the edge of the second        annulus.

After six months to one (1) year of the study, the group wearing thelenses produced by the method and design according to this inventionhave a 60% to 80% reduced or a slower group average rate of eye growththan the group average eye growth rate of the control group as measuredby the change (increase) in axial length or change (myopic shift) inauto-refraction over the same time period.

We claim:
 1. An ophthalmic lens for the slowing of myopia progressioncomprising: a) a convex surface with a central optic zone surrounded bya peripheral zone which is further surrounded by an edge zone, and aconcave surface which rests on the wearer's eye; b) the central opticzone including an inner disc, and a plurality of annuli, wherein a lenspower at any location in the central optical zone is described bysubtracting the optical power of a group of individual's eyes afterorthokeratology treatment from the optical power of the group ofindividual's eyes before orthokeratology treatment, wherein thesubtracting of the optical power of the group of individual's eyes afterand before orthokeratology treatment is calculated by acquiring andaveraging ocular wavefront data maps from a group of individual's eyesprior to orthokeratology treatment; converting the ocular wavefront datamaps from the individual's eyes prior to orthokeratology treatment to apre-treatment refractive power map by calculating the powers based onthe radial slopes along the visual axis through the pupil centers of theindividual's eyes; acquiring and averaging ocular wavefront data mapsfrom the individual's eyes after orthokeratology treatment; convertingthe ocular wavefront data maps from the individual's eyes afterorthokeratology treatment to a post treatment refractive power map bycalculating the powers based on the radial slopes along the visual axisthrough the pupil centers of the individual's eyes; subtracting thepre-treatment refractive power map from the post treatment refractivepower map to create a treatment map; averaging all of meridians of thetreatment map to generate a rotationally symmetric power map;alternately averaging the individual meridians of the treatment maptogether to generate a non-rotationally symmetric power map; trimmingthe rotationally and non-rotationally symmetric power-maps to a diametersubstantially corresponding to an optic zone of a contact lens; andforming the ophthalmic lens having the central optic zone with the powermaps incorporated therein.
 2. The ophthalmic lens of claim 1 wherein theinner disc has a diameter less than 2 mm.
 3. The ophthalmic lens ofclaim 1 wherein the optical power of the inner disc is substantiallyconstant.
 4. The ophthalmic lens of claim 1 wherein the plurality ofannuli comprises a first annulus having an outer diameter between 6.0 to7.0 mm.
 5. The ophthalmic lens of claim 1 wherein the plurality ofannuli comprises a first annulus and wherein the optical power of thefirst annulus is described by the equation:Power=0.486x ⁶−5.8447x ⁵+27.568x ⁴−65.028x ³+81.52x ²−51.447x+12.773where x is the radial distance from the center of the lens.
 6. Theophthalmic lens of claim 4, wherein the plurality of annuli comprises asecond annulus surrounding the first annulus and has an outer diameterbetween 7.25 and 7.75 mm.
 7. The ophthalmic lens of claim 6 wherein theoptical power of the second annulus decreases smoothly from the powerfound at the edge of the first annulus smoothly to between +2.00 and+3.25 D.
 8. The ophthalmic lens of claim 7, wherein the plurality ofannuli comprises a third annulus surrounding the second annulus and hasan outer diameter between 7.5 and 8.5 mm.
 9. The ophthalmic lens ofclaim 8, wherein the plurality of annuli comprises a fourth annulus, theoptical power of the fourth annulus is substantially constant with thepower found at the edge of the second annulus.
 10. The ophthalmic lensof claim 1 wherein the optical power of the eye data both after andbefore orthokeratology treatment is acquired from a total population.11. The ophthalmic lens of claim 1 wherein the optical power of the eyedata both after and before orthokeratology treatment is acquired from asub-population.
 12. The ophthalmic lens of claim 1 wherein the opticalpower of the eye data both after and before orthokeratology treatment isacquired from multiple corneal topography files.
 13. The ophthalmic lensof claim 1 wherein the optical power of the eye data both after andbefore orthokeratology treatment is acquired from an average of multiplewavefront files.
 14. The ophthalmic lens of claim 1 wherein the lenspower at any location in the optical zone is calculated by averaging allmeridians to a rotationally symmetric form.
 15. The ophthalmic lens ofclaim 1 wherein the lens power at any location in the optical zone iscalculated by averaging individual meridians to a non-rotationallysymmetric form.